When most people think of a burn injury, they think fire. But fire is only one example of how a person can sustain a burn injury. Other common types of burn injuries are caused by exposure to the sun, tanning bed lights, hot liquids or steam, hot metal, glass or plastic, and electrical shock. Burns are also caused by contact with chemicals, such as strong acids, alkalis, paint thinner or gasoline. Burns can be external or internal. Internal burns are those sustained as the result of inhaling smoke or chemical fumes causing damage to the mouth, throat and lungs.